Harmonic Balancer Replacement

The harmonic balancer on my 02 MP5 went out yesterday and I was wondering if it's an easy replacement task, have unmounted almost everything but still unsure about if I loose the timing. Have done before on my B2200 but thats old school. Any advice or write-up that helps me on this task?

just a tip, before you loosen the crank bolt, rotate the engine by hand until you have a "notch" not a "tooth" of the timing belt pointing straight at the ground. take a sheet of paper and cut out an "L" if you need to. just make sure that the mark you leave on the timing belt and block is perfectly perpendicular to the oil pan. mark that on the belt and block. mark exactly where the crank notch is sitting against the block. take zip ties and wrap them around the belt and the cam pulleys. 2 on each pulley is good. just so the teeth don't slip in the process. then from there you can take the balancer off and replace it. line up your marks and put everything back together. if all done correctly you should be on the road In no time.

Duren, thanks for the write-up, ended replacing all the front, seals, timing belt, idler, pulley, water pump, timing covers, valve cover gasket, harmonic balancer and p/s, a/c and alternator belts...$300 in parts plus labor to a friend because I didn't flet confortable doing it myself.

So... how does a Harmonic Balancer fail? I am curious.